In particular, the Achilles tendon which is a part extending from the calf muscle composed of gastrocnemius or calf functions suitably for walking depending on a pedestrian's actual needs by adjusting movements of the ankle joint according to relaxation and contraction of the muscle.
Such an Achilles tendon may be easily injured due to sudden shock or fatigue of the clay muscles in response to overstretching. Thus, it is preferably to relieve the tension in the Achilles tendon and the calf muscle after high impact sports such as a marathon.
It has been disclosed in Korean Utility Model No. 20-0409798 regarding a shoe for relieving the tension in the Achilles tendon and the calf muscle.
The conventional art is able to easily fall forward or backward when doing exercises in the forward flexion or backward extension postures because the entire sole of the shoe is formed in arc type. Furthermore, it is uneasy without stability when doing exercises for relieving the tension in the Achilles tendon and the clay muscle and exercise effects are also reduced because the user cannot keep a standing posture in the same position for a long time.